1. Field of the Invention
The field of the invention relates generally to temperature control of an emission control device in an engine exhaust system.
2. Background of the Invention
The inventors herein have developed an engine control methodology that allows efficient engine operation with some of the cylinders inducting air with no injected fuel. However, the inventors have also recognized that such operation may cool an emission control device coupled downstream of the engine. In other words, the high flow rate of gasses may carry away most of the heat, thereby reducing the device temperature below a required temperature for proper operation.